Parathyroidectomy may preserve kidney function in some patients with hyperparathyroidism

Key takeaways:

• Overall, parathyroidectomy did not affect long-term kidney function in older adults with primary hyperparathyroidism
• However, when done early, it may preserve function in patients aged younger than 60 years.

Parathyroidectomy had no significant impact on long-term kidney function among older adults with primary hyperparathyroidism, but if done early, it could preserve function in those aged younger than 60, according to researchers.

Primary hyperparathyroidism (PHPT) is a common endocrine disorder that has been linked to higher risks for chronic kidney disease (CKD), Carolyn D. Seib, MD, MAS, an assistant professor of surgery at Stanford Medicine, and colleagues wrote in Annals of Internal Medicine. To slow the progression of CKD, multidisciplinary guidelines recommend surgical removal of abnormal parathyroid glands — a parathyroidectomy — for patients with PHPT and an estimated glomerular filtration rate (eGFR) less than 60 mL/min/1.73 m².

However, the data regarding associations of long-term kidney function and parathyroidectomy are limited.

“Most patients with PHPT are not treated with parathyroidectomy, including those who meet operative guideline criteria based on CKD stage, highlighting clinical uncertainty about the effectiveness of parathyroidectomy as a management strategy to preserve kidney function,” the researchers wrote.

So, Seib and colleagues conducted a study to compare the incidence of a sustained decline in eGFR of at least 50% in patients with PHTP who underwent a parathyroidectomy compared with nonoperative management.

“We hypothesized that parathyroidectomy would be associated with a lower rate of having a sustained decline in eGFR of 50% or more after differences in baseline severity of PHPT and CKD risk factors between operatively and nonoperatively managed groups were accounted for,” they wrote.

The researchers emulated a hypothetical randomized trial — the target trial — by studying observational data from 43,697 adults diagnosed with PHTP.

Seib and colleagues found that, for older adults with PHPT, parathyroidectomy had no significant effect on long-term kidney function, and wrote that possible benefits related to kidney function should not be the main consideration for decisions about PHPT treatment.

Over the median follow-up period of 4.9 years, 6.7% of the participants with PHPT experienced a decline of at least 50% in eGFR. Regardless of how primary hyperparathyroidism was managed, the weighted cumulative incidence of eGFR decline was 5.1% at 5 years.

At 10 years, the weighted cumulative incidence of eGFR decline was 10.8% in patients managed with parathyroidectomy. The decline was 12% for those managed nonoperatively.

There was no significant difference in the adjusted hazard of eGFR decline among patients treated with parathyroidectomy vs. nonoperative management.

Subgroup analyses, however, indicated that, if treated with early parathyroidectomy, patients aged younger than 60 years were more likely to preserve long-term kidney function. In other words, parathyroidectomy was linked to a reduced hazard of long-term kidney function among patients aged younger than 60 years (HR = 0.75; 95% CI, 0.59-0.93) that was not apparent among those aged 60 years or older (HR = 1.08; 95% CI, 0.87-1.34).

Seib and colleagues wrote that their findings “add to our understanding of the risks and benefits of parathyroidectomy for PHPT,” as well as “advance our knowledge of appropriate indications for operative management.”

“When participating in shared decision making for older adults with PHPT, clinicians should not consider parathyroidectomy for potential benefits of preservation of kidney function,” they wrote. “For younger patients, clinicians should discuss the potential benefit of parathyroidectomy to reduce the risk for CKD and associated complications in adults with PHPT.”